Easy, fast and precise detection of particles such as cells is an important process in different fields e.g. at hospitals, companies working with bioreactors, cell research, drug discovery, breweries, dairies, breeding stations etc. On the market is a cell counting system “Nucleocounter NC-3000” (ChemoMetec, Allerød, Denmark) which is a small unit of 29×29×31 cm (H×W×D) including a full microscope and a sample entrance. The unit is connected to a computer comprising an image analyzing software. The NC-3000 system enables fast and precise automated detection at low magnification of cells by specific counting of nuclei, giving reproducible and accurate counts based on analyses performed with a fluorescence microscope.
The “NC-3000” can be used for viability and cell count, cell-cycle assay, mitochondrial potential assay, vitality assay, quantification of fluorescence intensity, fluorescence measurements from violet to far red, DNA fragmentation assay and GFP transfection efficiency assay.
Different microscope illumination techniques give different information in respect of a sample which is analyzed.
The inventors of the present invention have surprisingly found a solution of how to create and use a dark field light source unit which by itself is compact and which can be used in a compact microscope system such as the “Nucleocounter NC-3000” system and which is based on performing analyses at low magnification.